Apparatus for holding tip of band in strapping machine

ABSTRACT

A strapping machine comprising a table to place a package to be strapped thereon, being supported slidably along a guide piece disposed in the upper portion of the base section and being normally kept urged to move forwardly, a clip means installed to be optionally closed or opened for holding the leading end portion of the band between the opposing surface thereof and the surface of a groove defined on the under-side of said table when said clip means is fitted thereinto, said band is to be fed from under the table, directed upwardly in a direction perpendicular to the moving direction of the table and then led to make a loop to surround the table and the package therein, and an oscillating lever positioned under the table in order to be operated by a cam fixedly secured to a driving shaft for the purpose to cause the backward movement of the table after, upon being drawn back for tensioning thereof, said band is melted together by a suitable means at the opposing surfaces of the overlapping portions of the band and cut off.

[ 1 Dec. 3, 1974 APPARATUS FOR HOLDING TIP OF BAND IN STRAPPING MACHINE Yukio Takahashi, Tokyo, Japan [73] Assignee: Ikegai Tekko Kabushiki Kaisha, Tokyo, Japan 22 Filed: Feb. 22, 1973 21 Appl. No.: 334,855

[75] Inventor:

[30] Foreign Application Priority Data Feb. 25, 1972 Japan 47-23202[U] [52] US. Cl. 100/33 PB, 53/198 R [51] Int. Cl B65b 13/32 [58] Field of Search 100/33 R, 33 PB; 156/583; 53/198 R [56] References Cited UNITED STATES PATENTS 3,269,300 8/1966 Billett et al. 100/33 PB 3,368,323 2/1968 Wood 100/33 PB 3,397,105 8/1968 Takami 100/33 PB 3,470,814 10/1969 Tschappu.... 100/33 PB 3,494,280 2/1970 Kobiella 100/33 PB 3,577,910 5/1971 Feldkamp 100/33 PB 3,749,622 7/1973 Sato et al.... 100/33 PB 3,771,436 11/1973 Kaisha 100/33 PB Primary Examiner-Billy J. Wilhite Attorney, Agent, or Firm-Woodhams, Blanchard & Flynn [5 7 ABSTRACT A strapping machine comprising a table to place a package to be strapped thereon, being supported slidably along a guide piece disposed in the upper portion of the base section and being normally kept urged to move forwardly, a clip means installed to be optionally closed or opened for holding the leading end portion of the band between the opposing surface thereof and the surface of a groove defined on the under-side of said table when said clip means is fitted thereinto, said band is to be fed from under the table, directed upwardly in a direction perpendicular to the moving direction of the table and then led to make a loop to surround the table and the package therein, and an oscillating lever positioned under the table in order to be operated by a cam fixedly secured to a driving shaft for the purpose to cause the backward movement of the table after, upon being drawn back for tensioning thereof, said band is melted together by a suitable means at the opposing surfaces of the overlapping portions of the band and cut off.

4 Claims, 16 Drawing Figures PATENTEUCZC 31974 SHEET 1 W 7 FIG. IA PRIOR ART |O| PRIOR ART FIG. 4

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FIG. I4

APPARATUS FOR HOLDING TIP OF BAND IN STRAPPING MACHINE BACKGROUND OF THE INVENTION a. Field of the Invention The present invention relates to a strapping machine and more particularly to an apparatus for holding a tip of the band in a strapping machine for strapping a package by means of a heat sealing of the band.

b. Description of the Prior Art Heretofore, a strapping machine was used wherein a package is placed on the table which is slidably supported on a guide piece of an upper portion of a base section, and the tip of the band is held by the lower surface of the table and a clip installed under the table, and then they are surrounded and strapped by the band and the piling portions of the band are melted and sealed and thereafter the table and the clip are pulled out from between the package and the band. In this case, the tensile force of the band becomes a value obtained by multiplying a coefficient of friction with a press force against the band by means of the table and the clip. Accordingly, in order to increase the tensile force of the band, it becomes necessary to make the coefficient of friction bigger, and therefore, in the past, in order to obtain such increased value, a means as shown in FIG. 1A or FIG. 1B, was employed. Namely, in FIG. 1A, notches 103, 103' are respectively formed on the surface of the table 101 and the clip 102, and the tip of the band 104 is inserted between these notches so as to be held by them. It is impossible to increase the tensile force of the band 104 above the press force of the table 101 and the clip 102, and also in one case, the holding surfaces of the table 101 and the clip 102 are shaped as shown in FIG. 1B in which they are formed in V-shape or in other semi-circular shape and the like, and with this arrangement, strong tensile force is imparted to a small press force by means of the press force of the table and the clip and the deforming force of the band, but in this case, the tensile force of the band acts on the operating line of the press force, whereby strong press force is required in order to overcome such force and thus there are drawbacks that the structure of the machine has to be built rigid enough to withstand such force, and as a result, the entire size of the apparatus has to be made extremely large.

Under the circumstances, in order to eliminate the drawbacks of said conventional strapping machine, an apparatus for holding the tip of the band in the strapping machine which is similar to those appearing in the specifications and drawings of my company application U.S. Ser. No. 277,596 filed Aug. 3, 1972. However, even in such improved strapping machine, there were drawbacks that its structure was complicated and its manipulation was troublesome.

SUMMARY OF THE INVENTION The present invention has an object to provide an apparatus for holding a tip of the band in a strapping machine which is capable of eliminating the drawbacks of the conventional strapping machine as set forth above.

Another object of the present invention is to provide an apparatus for holding a tip of the band in the strapping machine whose structure is simple and being capable of lifting and lowering the clip automatically by responding to the forward and backward movement of the table.

A still another object of the present invention is to provide an apparatus for holding a tip of the band in the strapping machine in which a press rod is operated by a cam fixed to a shaft through an oscillating lever and a clip is caused to ascend by means of the press rod whereby its mechanism is relatively simple and is capable of imparting a relatively large press force in spite of the fact that the entire size of the apparatus is small.

BRIEF DESCRIPTION OF THE DRAWING In the accompanying drawings, FIGS. 1A and 1B are schematic drawings showing a holding portion of a conventional strapping machine.

FIG. 2 is a plan view of the general structure as having its top plate removed of an apparatus embodying the present invention.

FIG. 3 is an elevation view of the same apparatus as that in FIG. 2 as taken along the line IIIIII.

FIG. 4 is a longitudinal cross sectional view of a part in the vicinity of the roller shaft on an enlarged scale of the same apparatus as that in FIG. 2.

FIG. 5 is a front-view on an enlarged scale of the sealing device provided for the same apparatus as that in FIG. 2.

FIG. 6 is a partial view of a section as cut along the line VI VI of the same sealing device as that in FIG. 5. 7

FIG. 7 is a side-view of a section as cut practically along the center line of the base section of the same apparatus as that in FIG. 5 when the press member is in an upright position.

FIG. 8 is a partial view of a section as cut along the line VIII-VIII in FIG. 7.

FIG. 9 is an elevation view of a section as cut along the line IX-IX in FIG 7.

FIG. 10 is a plan view of a section as cut along the line X-X in FIG. 9.

FIGS. 11-15 are diagrams illustrative of the sequence of the working of the same sealing device as shown in FIG. 5.

DETAILED DESCRIPTION OF THE INVENTION The apparatus shown inthe accompanying drawings as an embodiment of the present invention may be divided broadly into two constituent devices, namely, the band-feeding device and the sealing device.

To begin with, the band-feeding device will be explained by reference to mainly FIGS. 2 and 3.

On one side of the base section 1, there is pivotally installed the reel 15 with the band b wound round it by means of the shafts l1 and 12. The shaft 11 is equipped with the magnetic brake 21 and the shaft 12 is equipped with the spring 14 coiled round it. At the time of exchanging the reel 15, the shaft 12 is taken outside the base section 1 in resisting to the pressure of this spring 14, whereby the reel 15 is disconnected from the shafts I1 and 12, and can be lifted, taken out and replaced with a new one.

On the opposite side of the base section 1, there is installed the reversible motor 2 which shaft is equipped with a couple of sprockets 3 and 3' said sprocket 3 being devised to transmit the turning effort to the sprocket l3 equipped for the shaft 11 and said sprocket 3' being devised to transmit the turning effort to the sprocket 5 mounted on the counter shaft 4 by means of the chains 18 and 19, respectively. The pulley 6 equipped on the counter shaft 4 is devised to transmit the turning effort to the pulley 9 of the feed roller shaft 7 supported by the casing 22 of the sealing device to be described later on through the belt 20. And, as shown in FIG. 3, the pulley 9 is installed on the shaft 7 through the free running clutch 10, said shaft 7 being equipped with the feed roller 8. The outer diameter of this feed roller 8 is so designed as to render the peripheral speed of the feed roller a little higher than the peripheral speed of the feed roller of band b wound round the reel at the time of said roller of band b having the maximum outer diameter, to insure that the band b between the feed roller 8 and the reel 15 never gets loose during the feeding of the band b, and the velocity difference between the feed roller 8 and the reel 15 is to be absorbed by the slip of the belt stretched between the pulleys 6 and 9. Meanwhile, in case of winding up the band b, the free running clutch works and the feed roller 8 does not rotate.

Next, the sealing device will be explained in the following.

Referring to FIGS. 5, 6 and 7, the press member 23 is oscillatably supported by the shaft 28 in the front of the casing 22 fixed on the base section 1. The guide hole 26 to pass the band b through it is provided vertically in about the center of this press member 23, and the opening 27 of said guide hole 26 is provided in about the center of the top end of the press member. The groove 24 to guide the band b is formed on a part of the round surface of the top end of the press member as divided by the opening 27, while the opposite part of said round surface as divided by the opening 27 constitutes the press surface 25 to press two ends of the band b. These two parts of the round surface of the top end of the press member 23 constitute an arc centering around the center of the shaft 28, and the opening 27 is so devised as to hold the heater 37.

Near the bottom inlet of the guide hole 26, there is provided the flanged press roller 38 which is pivoted on the lever 39 by means of the pin 40, said lever 39 being pivoted on the press member 23 by means of the pin 41. This press roller 38 is pressed against the feed roller 8 by the working of the spring 42 only when it is in abeyance as shown in FIGS. 4, 11 and 12.

The heater 37 is installed on the lever 43 which is pivoted on the lever 44 by means of the pin 45, while said lever 44 is pivoted on the press member 23 by means of the pin 46. And, the spring 49 is stretched between the pin 47 provided for the lever 43 and the pin 48 provided for the press member 23, whereby an ascending effort is imparted to the lever 44, while one end of the lever 44 is pushed against the stopper 50 fixed on a side wall of the casing 22 to thereby lower the lever 44 in resisting to said ascending effort and have the heater 37 held on the bottom of the opening 27 of the press member 23. Besides, for the purpose of preventing the heater 37 from coming into direct contact with the bottom of the table 52 when the lever 44 is parted from the stopper 50, the pin 51 to restrict the ascent of the leve 44 is provided for the press member 23.

Referring to FIGS. 7, 8, 9 and 10, the back of the press member 23 is provided with the arm 31 having the slot 71 and fitted on the shaft 28 and the pin 34. The slide piece 32 slidably fits in this slot 71, and the pin 33 of said slide piece 32 is fixed on the disc 30. The shaft 29 of this disc is pivoted on the casing 22 and is also connected with the cam and coupling 35 to be rotated by the motor 36.'With one rotation of this shaft 29, the press member 23 performs one reciprocating motion as shown in FIG. 8, whereby one stroke of strapping operation is completed.

Referring to FIGS. 7 and 10, the table 52 is slidably laid between the guide pieces 53 and 54 fixed on top of the casing 22, and is devised to be pushed by the spring 55 disposed between the plate 72 fixed 0n the guide piece 54 and the projection 73 provided for the table 52 and advance until said projection 73 strikes the stopper 57 provided for the guide 54. When the table 52 has thus advanced, its front end is so located as to cover the top of the press member 23. And the bottom side of this table 52 is provided with an arched dent practically agreeing with the round surface of the top of the press member 23 and a groove in which the clip 58 for the purpose of holding down the band b is to fit (see FIG. 11). The Projection 74 is also fixed to this side.

The above described structure and the operation thereof is substantially identical to the structure disclosed in my copending application Ser. No. 277,596.

The base end of the clip 58 is pivoted on said projection 74 provided for the table 52 by means of the pin 59, and the press rod 68 that moves vertically on the lower surface of the clip 58 is placed on the upper surface of the lever 69, and said lever 69 is pivotally supported on the casing 22, and the cam roller 76 is pivotally supported at the other end by means of the pin 75, and this cam roller 76 is engaged with the plate cam 67 fixed to the shaft 29 of the coupling 35 to move the clip 58 vertically.

The pin 60 is fixed on the projection 74 of the table 52, and the lever 61 which upper part confronts the pin 60 is pivoted on the casing 22 by means of the pin 62. The cam roller 63 is pivoted on the lower end of this lever 61 by means of the pin 64, and said cam roller 63 is devisedto be kept in contact with the surface of a face cam 66 which is fixed on the shaft 29 by means of the torsion spring 65 coiled round the pin 62. With the rotation of the cam 66, the lever 61 turns anticlockwise in FIG. 7.

I-Iereunder will be given an elucidation of the working of the present machine by reference to FIG. 11 and so forth.

FIG. 11 shows the state of the package a as put in a loop of the band 12 and laid on the top plate of the base section. Prior to this, the press member 23 has come to a halt in the position as shown in the drawing, the clip 58 has ascended to be open and the tip of band b has been suspended in the middle of the guide hole 26 of the press member 23. At this, the motor 2 starts normal rotation to turn the feed roller 8 and the reel 15 in the direction of the arrow respectively and thrust out the band b through the opening of the top of the press member 23 via the guide hole 26 of said press member 23. At this, the operator leads the band b by hand to the top side of the clip 58 which has ascended through the void formed between the guide groove 24 and the recess 17 of the bottom side of the table 52. When the cams 66 and 67 fixed to the shaft 29 of the coupling 35 are rotated in the direction of the arrow as shown in FIG. 7 by turning the motor 36, the cam roller 76 engaged with the plate cam 67 rides over the portion of projection of the cam 67 and then the lever 69 pivotally supported with its one end to the casing 22 is caused to ride over the projection and the press rod 68 placed on the lever is caused to ascend, and thus the clip 58 is lifted whereby the tip of the band b is held in the groove 16 of the table 52, and the feeding of the band b is con tinued, and a necessary loop is formed on the top plate of the base section 1 and the table 52 to thereby put the package a in the loop.

FIG. 12 shows the state of the band b when it has been pulled back. After the operation described in the foregoing, the motor 2 is rotated in the reverse direction. With this, the feed roller 8 and the reel also turn in reverse direction to pull back the band b,

whereby the package a is strapped. On this occasion,

the magnetic brake 21 clamps the shaft 11 of the reel 15.

FIG. 13 shows the state of the press member 23 during its forward stroke and the heater 37 in the course of sealing the band b. To be precise, the motor 36 is moved and the disc 30 rotates to turn the arm 31 anticlockwise (see FIG. 7), whereby the press member 23 also oscillates anticlockwise centering around the shaft 28. With this, the guide groove 24 of the press member 23 disengages from the table 52, that is, from the band b. At the same time, the lever 44 parts from the stopper 50, and turn clockwise centering around the pin 46 until it is brought into contact with the pin 51 by the tensile force of the spring 49. As a result, the lever 43 pivoted on the lever 44 by means of the pin 45 ascends, and the heater 37 held on it contacts with the upper section b' and the lower section b" of the band b and moves in concert with the oscillation of the press member 23 while melting said two sections b' and b" Following in the wake of this heater 37, the press surface 25 moves while pressing the melted two sections b and b" and sealing them.

On this occasion, the reel 15 is suspended, but the press roller installed on the lower part of the press member 23 moves centering around theshaft 28 to go away from the feed roller 8, and, accordingly the band b is automatically supplied by the length equivalent to the distance covered by said movement of the press roller.

' FIG. 14 shows the state of the band b when it has been sealed. With the progress of the process of sealing the band b as set forth above, the speed of the press member 23 decreases and, since the heater 37 is still in engagement with the band portion b" the heater remains in contact with a point on the band portion b" thereby causing deep melting of the band. As the press member 23 stalls, the cam roller 76 engages the bottom portion of the cam 67 as shown in FIG. 9 as the rotation of the shaft, namely, the cams 66 and 67 continues to oscillate the lever 69 in the lower direction, and the press rod 68 is descended to stop the pressure of the clip 58, and whereby the clip 58 is oscillated in the lower direction by the press force of the spring 56 and the own weight of the clip whereby the clip is opened and the lever 61 is turned anticlockwise in FIG. 7 centering around the pin 62 by means of the cam 66, and the upper end of said lever 61 makes the table 52 and the clip 58 retreat, and slips out of the band b. As a result, the tension of the band b is temporarily increased, and by virtue of the thus increased tension, the band b is severed at its most deeply melted point.

FIG. 15 shows the state of the press member 23 when it has completed the backward stroke. With the progress of the rotation of the aforesaid disc 30, the press member 23 rapidly oscillates clockwise opposite to the previous direction, the lever 44 contacts with the stopper 50 to turn in the direction opposite to the previous direction, and the lever 44 along with the heater 37 held thereon decend to be again supported within the opening 27 of the press member 23 again. On this occasion, the lever 61 returns to the position shown in FIG. 6, whereby the table 52 and the clip 58 also advance again, and the clip 58 descends to its normal position as shown in the dotted line in FIG. 7. And, as the press roller38 has returned from the position shown in the dotted line to the position shown in the solid line in FIG. 15 while the reel 15 is in abeyance and does not work to feed the band, the portion of the band b existing inside the guide hole 26 of the press member 23 is pulled down to the extent equivalent to the distance of travel made by the press roller 38 going away from the reel 15, and its tip parts rapidly from the heater 37to retreat up to almost the middle of the guide hole 26.

Through the foregoing procedure, a cycle of the working of the band b to strap the package a is completed, and by repeating this cycle, the strapping of package a can be performed successively.

Although particular preferred embodiments of the present invention have been disclosed hereinabove for the purpose of illustration, it will be understood that variations or modifications thereof which lie within the scope of the present invention as defined by the appended claims are fully contemplated.

What is claimed is 1. In a strapping machine for securing a flexible band in surrounding relationship to an object, such as a package, said machine including a frame having a table slidably supported thereon for movement between first and second positions, the table being adapted to have a package disposed on the upper surface thereof, clip means mounted on said frame for movement between open and closed positions, said clip means including a movable clip portion disposed for coaction with the undersurface of said table for holding the leading end of a band therebetween when said clip means is in said closed position, means associated. with said table and disposed at least partially thereunder for feeding said band upwardly to make a loop surrounding the table and a package thereon, drive means for controlling the slidable movement of said table between said first and second positions, said drive means including a rotatable shaft and linkage means coacting between said shaft and said table, means coacting with the band for melting the opposing surfaces thereof and for causing the opposing melted surfaces to be overlapped and pressed together to create a bond therebetween, and control means coacting with said clip means for controlling the opening and closing thereof, comprising the improvement wherein said control means includes link means coacting directly between said shaft and said clip means for controlling the opening and closing thereof.

2. An apparatus according to claim 1, wherein said link means includes a cam secured to said shaft and rotatable therewith.

3. An apparatus according to claim 2, wherein said link means includes a lever member pivotally supported on said frame and having one end thereof disposed in engagement with said cam, whereby rotation of said shaft and said cam causes swinging movement 4. An apparatus according to claim 3, wherein the linkage means for controlling the table movement includes a further cam fixedly secured to said shaft for rotation therewith and a lever pivotally supported on said frame and coacting between said further cam and said table. 

1. In a strapping machine for securing a flexible band in surrounding relationship to an object, such as a package, said machine including a frame having a table slidably supported thereon for movement between first and second positions, the table being adapted to have a package disposed on the upper surface thereof, clip means mounted on said frame for movement between open and closed positions, said clip means including a movable clip portion disposed for coaction with the undersurface of said table for holding the leading end of a band therebetween when said clip means is in said closed position, means associated with said table and disposed at least partially thereunder for feeding said band upwardly to make a loop surrounding the table and a package thereon, drive means for controlling the slidable movement of said table between said first and second positions, said drive means including a rotatable shaft and linkage means coacting between said shaft and said table, means coacting with the band for melting the opposing surfaces thereof and for causing the opposing melted surfaces to be overlapped and pressed together to create a bond therebetween, and control means coacting with said clip means for controlling the opening and closing thereof, comprising the improvement wherein said control means includes link means coacting directly between said shaft and said clip means for controlling the opening and closing thereof.
 2. An apparatus according to claim 1, wherein said link means includes a cam secured to said shaft and rotatable therewith.
 3. An apparatus according to claim 2, wherein said link means includes a lever member pivotally supported on said frame and having one end thereof disposed in engagement with said cam, whereby rotation of said shaft and said cam causes swinging movement of said lever member, said link means also including rod means slidably supported on said frame for movement at least partially in a vertical direction, said rod means having the upper end thereof disposed in engagement with said clip means and having the lower end thereof disposed in engagement with said lever member.
 4. An apparatus according to claim 3, wherein the linkage means for controlling the table movement includes a further cam fixedly secured to said shaft for rotation therewith and a lever pivotally supported on said frame and coacting between said further cam and said table. 